Management of acute periprosthetic joint infection of the knee – Algorithms for the on call surgeon

Periprosthetic joint infection (PJI) remains a serious complication following a total knee replacement. Infections rates following arthroplasty range from 0.5% to 3%. The acutely infected knee replacement often presents to the on call Orthopaedic Surgeon who can often lack the expertise or resources for the definitive management. However, obtaining an early and accurate diagnosis and potentially performing an early treatment such as irrigation and debridement may be required by the on call surgeon. Management of these patients should include a team of specialists including Medical or Intensive Care, and Infectious Disease. Management of PJI is expensive, complicated and has a high morbidity. These patients should have their definitive care by specialist multidisciplinary teams on a regional basis.     

The Influence of Obesity on the Outcome of TKR: Can the Impact of Obesity be justified from the Viewpoint of the Overall Health Care System?

Background

There is controversy in the literature regarding the justification of performing total knee replacement (TKR) in obese patients in view of their increased risk of poor outcomes and how those poorer outcomes impact the health care system overall.

Questions/Purposes

Is TKR justifiable in the obese patient? Can the negative impact of continuing to perform TKR in the obese be quantified?

Methods

A Cochrane Library, PubMed (MEDLINE), and Google Scholar search related to the justification of TKR in the obese patient and its impact on the health care system was analyzed. The main criteria for selection were that the articles were focused in the aforementioned questions.

Results

Two thousand one hundred seventy-three articles were found, but only 50 were selected and reviewed because they were focused on the questions of this paper. Although some articles (with low grade of evidence) did not find that obesity adversely affected the outcome of TKR, most of them found that obesity adversely affected the results of TKR. Regarding complications rates and survival rates, obesity has shown to have a negative influence on outcome after TKR. The improvements in patient-reported outcome measures, however, were similar irrespective of body mass index. Regarding the impact of TKR in obese patients, an extra cost of US$3,050 has been reported per patient. Considering that 50% of the US population is obese and that 600,000 TKRs are implanted per year, the impact for the US health system could be as much as 915 million dollars (300,000 × 3,050).

Conclusion

TKR in obese patients may be justifiable because the functional improvements appear equivalent to those of patients with a lower BMI. However, in obese patients, the risk of complications is higher and the prosthetic survival is lower. Moreover, TKR in obese patients has a huge impact on the health system which should be considered.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-014-9385-9) contains supplementary material, which is available to authorized users.     

Free uroflowmetry versus “Do-It-Yourself” uroflowmetry in the assessment of patients with lower urinary tract symptoms

Introduction

We investigated the possibility that patients could carry out a urine flow assessment at home by themselves, in comfort, without expense and without the use of equipment. We compared this strategy of “Do-It-Yourself” (DIY) uroflowmetry with traditional, hospital uroflowmetry.

Materials and methods

One hundred and twenty patients were enrolled. The patients underwent conventional, free uroflowmetry in hospital. Subsequently, the patients were asked to carry out the following procedure at home: urinate into a graduated container to quantify the total voided volume and determine the flow time by measuring the duration of miction with a stopwatch or simply with the second hand of a clock. This procedure had to be performed three times without preparation.

Results

Hundred patients completed the study. The mean age of the patients analysed was 64.12 years. Their free uroflowmetry values were as follows: the mean voiding time was 44.28 s, the mean voided volume was 290.92 ml, the mean Qmax was 15.17 ml/s, the mean Qmean was 7.87 ml/s, and the mean post-void residual volume was 78.44 ml. The mean Qmean measured by the “DIY-uroflowmetry” was 8.33 ml/s, which was not statistically significantly different (P = 0.12). Assuming that pathological hospital uroflowmetry values are equivalent to a DIY-Qmean ≤10 ml/s and that normal hospital values are equivalent to a DIY-Qmean >10 ml/s, the concordance was 100 %.

Conclusions

Our proposed DIY evaluation of urine flow, together with the International Prostatic Symptom Score (IPSS), provides a good estimate of the results of free uroflowmetry, enabling unnecessary hospital investigations to be avoided.     

Ahlbäck grading of osteoarthritis of the knee: poor reproducibility and validity based on visual inspection of the joint

BACKGROUND: Staging of osteoarthritis (OA) of the knee is commonly based on the Ahlb?ck classification. Its value has been questioned, however. We therefore evaluated the reproducibility and validity of this classification of knee osteoarthritis. PATIENTS AND METHODS: 48 patients (48 knees) (medial OA: n = 30; lateral OA: n = 8) operated with total knee prostheses were studied. Weight-bearing radiographs were evaluated twice by 4 observers. Presence of bone attrition on radiographs was compared with observations of the resected parts of the distal femur and proximal tibia. RESULTS: When the same observer classified the radio-graphs twice according to Ahlb?ck, the repeatability was fair in both medial OA (kappa values = 0.15-0.65) and lateral OA (0.59-0.76), and between different observers it was poor (kappa: 0.1). Comparison between radiographic classification and classification based on visual inspection of the bone pieces removed during arthroplasty revealed an acceptable sensitivity in both medial (67-95%) and lateral OA (43-86%), but the specificity was low (medial: 11-67%; lateral: 25-75%). INTERPRETATION: The main problem with the Ahlb?ck classification was that a joint space could often be seen radiographically despite the presence of bone attrition on the preparations. According to our study, conventional radiographs do not give sufficient information for correct grading.     

Ahlbäck grading of osteoarthritis of the knee: Poor reproducibility and validity based on visual inspection of the joint

Background?Staging of osteoarthritis (OA) of the knee is commonly based on the Ahlbäck classification. Its value has been questioned, however. We therefore evaluated the reproducibility and validity of this classification of knee osteoarthritis.

Patients and methods?48 patients (48 knees) (medial OA: n?=?30; lateral OA: n?=?8) operated with total knee prostheses were studied. Weight-bearing radiographs were evaluated twice by 4 observers. Presence of bone attrition on radiographs was compared with observations of the resected parts of the distal femur and proximal tibia.

Results?When the same observer classified the radio-graphs twice according to Ahlbäck, the repeatability was fair in both medial OA (kappa values = 0.15–0.65) and lateral OA (0.59–0.76), and between different observers it was poor (kappa: 0.1).

Comparison between radiographic classification and classification based on visual inspection of the bone pieces removed during arthroplasty revealed an acceptable sensitivity in both medial (67–95%) and lateral OA (43–86%), but the specificity was low (medial: 11–67%; lateral: 25–75%).

Interpretation?The main problem with the Ahlbäck classification was that a joint space could often be seen radiographically despite the presence of bone attrition on the preparations. According to our study, conventional radiographs do not give sufficient information for correct grading.     

The forgotten foot – An assessment of foot and ankle radiograph pathology in final year medical students

IntroductionIt has been shown that doctors in Emergency Departments (EDs) have inconsistent knowledge of musculoskeletal anatomy. This is most likely due to a deficiency in focused musculoskeletal modules at undergraduate level in medical school. The aims of this study were to evaluate the knowledge of final year medical students on foot anatomy and common foot and ankle pathology as seen on radiographs.MethodsFinal year medical students were asked to complete our short examination on a handout. The handout was anonymous and non-mandatory. There were four images. The first image is the anatomical section and the remaining images are the pathological section.ResultsAll 235 students responded. 57% were females. For the identification of the normal bones of the foot as shown on an X-ray, the average score for the group was 2.69 (out of a maximum of 6) {SD 1.67}7. Only 8.3% achieved a 6/6 or 100% grade i.e. recognising all six bones correctly. A further 8.3% achieved 5/6 (83%). 8.3% failed to correctly identify any bone seen on the X-ray, a corresponding score of 0.DiscussionThis quick test showed normal anatomy of the foot and common pathology. One would expect final year medical students to be familiar with, especially two weeks before their finals in surgery. The curriculum should address the paucity of time spent in educating students in foot and ankle pathology.     

Pathology and therapy of the “shoulder joint complex”

A synopsis of the mechanics, pathology and therapy of the shoulder joint complex is given. Some new methods of treatment are indicated, including the barbed splint, the redression corset and physiotherapy.     

“High ankle block” for surgery at the ankle joint

BackgroundSurgery around the ankle is increasingly embedded in outpatient treatment concepts. Unfortunately, the classic “ankle block” as a concept of regional anesthesia is inappropriate for surgery around the ankle because the injection sites are too distal to block this specific region.MethodsThe “high ankle block” avoids this disadvantage by dislocating the injection points 15 cm proximal to the malleoli. Three of five peripheral nerves necessary to perform the block can be reached by a circumferential subcutaneous wall. The Posterior Tibial Nerve and the Deep Peroneal Nerve are addressed by an ultrasound guided approach.ResultsThe efficacy of the technique is highlighted by a case series (3 cases) in which the new blockade was used as a stand-alone procedure, i.e. without additional general anesthesia.ConclusionsThe “high ankle block” may serve as an ultrasound guided expansion to the classic techniques, extending the operative spectrum to the ankle region.     

Microfracture for the treatment of cartilage defects in the knee joint – A golden standard?

The evidence for the effectiveness of the microfracture procedure is largely derived from case series and few randomized trials. Clinical outcomes improve with microfracture for the most part, but in some studies these effects are not sustained. The quality of cartilage repair following microfracture is variable and inconsistent due to unknown reasons. Younger patients have better clinical outcomes and quality of cartilage repair than older patients. When lesion location was shown to affect microfracture outcome, patients with lesions of the femoral condyle have the best clinical improvements and quality of cartilage repair compared with patients who had lesions in other areas. Patients with smaller lesions have better clinical improvement than patients with larger lesions. The necessity of long postoperative CPM and restricted weight bearing is widely accepted but not completely supported by solid data. Maybe new developments like the scaffold augmented microfracture⁶ will show even more consistent clinical and biological results as well as faster rehabilitation for the treatment of small to medium sized cartilage defects in younger individuals.All in all there is limited evidence that micro fracture should be accepted as gold standard for the treatment of cartilage lesions in the knee joint. There is no study available which compares empty controls or non-surgical treatment/physiotherapy with microfracture. According to the literature there is even evidence for self regeneration of cartilage lesions. The natural history of damaged cartilage seems to be written e.g. by inflammatory processes, genetic predisposition and other factors. Possibly that explains the large variety of the clinical outcome after micro fracture and possibly the standard tools for evaluation of new technologies (randomized controlled trials, case series, etc.) are not sufficient (anymore).Future technologies will be evaluated by big data from international registries for earlier detection of safety issues, for detection of subtle but crucial co-factors for failure and osteoarthritis as well as for lower financial burdens affecting industry and healthcare systems likewise.     

The “forgotten” goiter after total thyroidectomy

INTRODUCTION“Forgotten” goiter is an extremely rare disease which is defined as a mediastinal thyroid mass found after total thyroidectomy.PRESENTATION OF CASEWe report two cases with forgotten goiter. One underwent total thyroidectomy due to thyroid papillary cancer and TSH level was in normal range one month after surgery. The thyroid scintigraphy scan revealed mediastinal thyroid mass. The second case underwent total thyroidectomy due to Graves’ disease and TSH level was low after surgery. At postoperative seventh year, patients were admitted to our Endocrinology Division due to persistent hyperthyroidism and CT scan revealed forgotten thyroid at mediastinum. Both patients underwent median sternotomy and mass excision, there was no morbidity detected after second surgical procedures.DISCUSSIONIn the majority of cases forgotten goiter is the consequence of the incomplete removal of a plunging goiter. Although in some cases, it may be attributed to a concomitant, unrecognized mediastinal goiter which is not connected to the thyroid with a thin fibrous band or vessels. Absence of signs like mediastinal mass or tracheal deviation in preoperative chest X-ray do not excluded the substernal goiter.CONCLUSIONRetrosternal goiter should be suspected if the lower poles could not be palpated on physical examination and when postoperative TSH levels remained unchanged.